In May, Instagram designers, engineers and product managers brainstormed ideas on how to make shopping work in the app. Now, six months later, they’re introducing the winning idea: Brands can tag products in their photos, much the way users tag friends. A single tap will reveal more information about the product, and another tap will send you to the retailer’s site to buy the product. After the launch, Instagram will gather data from how consumers use the new feature to improve it.

Bloomberg reports that Instagram vice president of monetization James Quarles enumerated future possibilities for the e-commerce feature, including the addition of comparison shopping, another way to search for products on the app, “or even a Pinterest-like feature to save posts that inspire.”

“We are so well-positioned in this space,” said Quarles. “Instagram is super visual, we have a well-defined graph of your interests based on what you’re following, and the serendipity of discovery happens every day through the ad products and who you follow.”

Instagram is aiming to go international with the e-commerce feature, and add video, but for now it’s being rolled out in a contained version. Only 20 brands are on board — including Kate Spade, Warby Parker and J.Crew — and the company isn’t yet taking “any cut of the proceeds.” For J.Crew, the app “fills a gap in mobile shopping.” The fact that it’s image-based, said J. Crew president/creative director Jenna Lyons, “makes it much more amenable to inspiring people to buy products than Facebook.”

“It’s been a little frustrating to us in the past to not be able to have people purchase on Instagram,” she said. “Not only has it become a place for people to get influenced by their friends, but they’re walking into our stores with their phones and saying, do you have this?”

Adding an e-commerce feature makes sense since people have “long been shopping on Instagram without a formal way to buy things.” That includes influencers posting photos of fashion and users taking screenshots of products they love and direct-messaging the photos to themselves.

The caveat is that shopping has a history of not working well on social media. Facebook’s previous attempts in e-commerce — including birthday gifts and Facebook credits, a virtual currency for games — were discontinued. More recently, Facebook’s launch of Marketplace crashed when people started to use it to post ads for drugs, sex and exotic animals. Twitter’s “buy button” didn’t work, and Pinterest, which made a bigger investment in shopping, allows direct buying on its site, “but it’s still unclear how popular the tool is with consumers.”

Quarles response is that, “Instagram aims to learn from all these experiences — especially from its parent company, Facebook, which has shared its notes.”